Fbancis w



(No Model.)

P. W. JONES.

DYNAMO TELEGRAPHY.

Np. 381,251. Patented Apr. 17, 1888 INVE TO Q BY j I v A/TTORNEYS" N4 PEIERS, Phglolhhagmphlr, Wauhinglnn. 0.0

ate together or simultaneously by mounting UNITED STATES PATENTOFFIcE.-; j

ra Noi's w. JONES, on NEW YORK, N. Y.

. DYNA MOj-TE LEGRA PHYI SPECIFICATION forming part 'ofIietters Patent No. 381,251, dated April 1-7, 1888. Application filed November 11,1887. Serial No. 254,930. '(No modeLl- P To all whom it may concern: Be it known that l, FRANCIS JoNEs, a citizen of the United States, and a resident of New York, in the county of New York and State of New York, have invented a certain new and useful Improvement in Dynamo-Telegraphy, of which the following is a specification. I V

My invention relates to the key system of to employment in duplex or quadruplex' tele-. graphs where dynamo-machines or secondary batteries are employed as the source of electric energy. a r

The object of the invention is to provide a simple and effective arrangement of apparatus whereby the desired reversals of polarity 1 and changes of tension may be produced on the line; and to this end it consists in the'combination, with two simultaneously-operating v, two-p.ointkeys, each connected at its front and back contacts, respectively, with sources of different polarity, and governing,respectively, the flow of currents of different tension to line,

double key and the line, and having its front contact connected to one part of the doubly-acting key, while its other contact is connected to the other part of said key. The arrangement Fig. 2 illustrates a modification of the double one ofv the parts of the other key is connected I tothekeyG. t It is to be understood that the intervals be-fgo key.

A B indicate two key-levers, or keys having two contacts, closed separately and according to the position of the key, after the manner Well understood in' the art, one contact being technically the front? and the other the back contact. The key-levers are insulated from one another,and are made to operupon a common support or center; In Fig. 2 the simultaneous action isobtained by working the two levers by magnets, both in the 50 same local circuit, controlled by a key. Other telegraphs, and is more especially designed for of B connects with a source of the same tenof a two-point key interposed between the means might be employed. The lever A, when onits back contact, connects with a source of current of, say, positive polarity, and .0f,-say, three hundred volts. Its front contact connects'with a source of current of opposite polarityand substantially the same tension. This key, if connected directly to a cirouit, would, when operated, simply producere "versals of current of a giventension. a Lever B has its front contact connectedsimilarly to a source of current of positive polarity, but of a different tension from that with which lever A is connected. The back contact sion as its front contact, but of opposite polarity. This key would likewise serve, when connected directly to a circuit, to produce alternations'of polarity-in a current of given ten= sion different from that controlled byA.

Key;lever 'A connects with the backor rest 70 contact of a key, 0, and lever B with-the front oropen contact of the same key. Key C is connected to the line. the double key A B is. operated, reversals of current take place, these reversalsbeing re versals of a current whose tension is that of the lever B. When the keyG is operated,the reversals will still takeplace, being new pro- ,duced ,by the action of the lever 'A'; but their tension is different, as before explained. The operator' controlling transmitter A B vmay therefore continue to send his message by rei I 'versals of polarity, despite the movement of key 0, and the operator controlling C may at, pleasurevarythe tension ofthe current. for the purpose of sending his own message, the tension beingdependent,obviously,upon which tween break of back contact and closure of front contact, and viceversa, with all the When itisatr'estand. a

What I claim as my invention is- The combination, with atransmitting device having two sets of front and back contacts, of two sources of electricity of substantially the same tension, but opposite polarity,'whose connections with the circuit are governed, re-

spectively, by one set of contacts, two other sources of current, also of opposite polarity, but

of different tension from the first, similarly governed by the second set of contacts, and a second back and front contact transmitterthat in its normal position closes the connection for FRANCIS W. JONES.

Witnesses:

WM. H. GAPEL, H. O. TOWNSEND. 

